There’s no numerical evidence that Facebook has "lost its cool," but you can feel it. You hear people talking about it. Instead of seeing Facebook blue illuminating the phones of fellow subway and bus riders, you see Instagram or Snapchat or Twitter. Facebook has become a normal thing — a "social utility" everyone uses but few are excited about.

The only thing Hamburger gets wrong there is that there is numerical evidence that Facebook has "lost its cool."

Check out this chart.

It's sourced from a survey of more than a thousand teenagers.

It shows that Tumblr has passed Facebook as their most-used social network: